Goldfish have long been one of the most popular pet fish, often thought of as beginner-friendly and low-maintenance. But as I discovered after years of keeping goldfish, there’s a lot more to these fish than most people think. Unfortunately, many misconceptions can lead to poor care or even shortened lifespans. In this guide, I’ll debunk some of the most common myths about keeping goldfish and share the facts to help you provide the best possible care for your goldfish.
Myth 1: Goldfish Can Live in Bowls
Fact: Goldfish Need Large, Filtered Tanks
One of the biggest and most harmful myths is that goldfish can thrive in small, unfiltered bowls. You’ve probably seen pictures of goldfish swimming in tiny bowls, but the truth is, this is far from ideal. Goldfish are large, messy fish that need plenty of space and a good filtration system to stay healthy.
- Why tanks are better: Goldfish produce a lot of waste, which leads to ammonia buildup. Without a proper filter, that ammonia can quickly reach toxic levels. Goldfish also grow quite large—up to 6-10 inches (15-25 cm) for most varieties, and even larger for fancy breeds like the comet.
- Recommended tank size: At a minimum, a single goldfish needs a 20-gallon tank, with an additional 10 gallons for each extra fish. If you have the space, a 40-gallon tank or larger is even better.
If you’re setting up a goldfish tank, here’s a guide to get started: How to Set Up a Goldfish Tank.
Myth 2: Goldfish Have Short Lifespans
Fact: Goldfish Can Live Over 20 Years
Many people believe that goldfish only live a few months or maybe a couple of years. I used to think the same until I realized that, with proper care, goldfish can live for decades! In fact, the oldest recorded goldfish lived to be 43 years old.
- Why do some goldfish die young? In most cases, short lifespans are the result of poor living conditions, such as small tanks, bad water quality, or lack of proper nutrition. When goldfish are given the right environment and care, they can easily live 10 to 20 years, or even longer.
For more tips on extending your goldfish’s lifespan, check out Goldfish Care for Long Life.
Myth 3: Goldfish Don’t Need a Filter
Fact: A Filter is Essential for Goldfish Health
Goldfish are notorious for being messy eaters and producing a lot of waste. This waste leads to ammonia buildup in the tank, which can quickly become toxic to the fish. Without a filter, maintaining clean, healthy water is nearly impossible, and frequent water changes won’t be enough to keep up with the waste load.
- Why filters are necessary: A good filter helps remove harmful chemicals like ammonia and nitrite, and it also provides oxygenation through water movement. Even if you’re doing weekly water changes, a filter is essential for keeping the water safe and clean for your goldfish.
If you’re looking for the right filter for your goldfish tank, check out Best Filters for Goldfish Tanks.
Myth 4: Goldfish Are Coldwater Fish and Don’t Need a Heater
Fact: Goldfish Thrive in Cooler Water, But Temperature Stability is Key
Goldfish are indeed considered coldwater fish, meaning they can thrive at lower temperatures compared to tropical species. However, it’s important to remember that they still need a stable temperature to stay healthy. Sudden temperature swings, even in cooler water, can stress your goldfish and make them more susceptible to illness.
- Ideal temperature range: Goldfish do well in water temperatures between 65°F and 75°F (18°C to 24°C). If the temperature in your home fluctuates a lot, or if the water gets too cold (below 60°F or 15°C), you may need to use a heater to maintain stability.
Learn more about maintaining the right water conditions here: How to Stabilize Water Temperature in Goldfish Tanks.
Myth 5: Goldfish Only Grow to Fit Their Tank
Fact: Goldfish Will Stunt in Small Tanks, Leading to Health Issues
There’s a common misconception that goldfish will only grow as large as their tank allows. While it’s true that goldfish in small tanks often stay small, this is not because the tank is “controlling” their size. Instead, the fish’s growth is stunted, which can cause serious health problems over time.
- Why stunting is dangerous: When a goldfish is kept in a small, overcrowded tank, the buildup of waste and toxins can inhibit their natural growth. However, their organs continue to grow, which leads to deformities and a shorter lifespan. Proper tank size and water quality are key to ensuring that goldfish can grow to their full potential.
For more information on why tank size matters, check out Goldfish Tank Size Guide.
Myth 6: Goldfish Don’t Need Special Food
Fact: Goldfish Have Specific Dietary Needs
It’s easy to assume that goldfish can eat just any kind of fish food. However, goldfish have specific dietary needs, and feeding them the wrong type of food can lead to digestive issues or malnutrition.
- Best diet for goldfish: Goldfish are omnivores, meaning they need a balanced diet of both plant and animal matter. Look for high-quality goldfish-specific pellets or flakes, which are designed to meet their nutritional needs. In addition, offering fresh vegetables like peas (with the skins removed) or leafy greens is a great way to give them a varied diet.
I also recommend avoiding overfeeding, as this can cause water quality issues and digestive problems. Here’s a helpful guide on Feeding Goldfish Properly.
Myth 7: Goldfish Can Live with Any Other Fish
Fact: Goldfish Need Careful Tank Mates
Goldfish are generally peaceful fish, but they are coldwater fish, which means they don’t do well with many common tropical species that need warmer water. Additionally, goldfish can grow large and sometimes outcompete other fish for food, especially slower or smaller species.
- Good tank mates for goldfish: If you want to keep other fish with your goldfish, look for coldwater species that can tolerate similar conditions. Examples include White Cloud Mountain Minnows, Dojo Loaches, or other goldfish varieties. Avoid pairing them with tropical fish or aggressive species that could stress them out.
For a full list of compatible tank mates, check out Best Tank Mates for Goldfish.
Myth 8: Goldfish Don’t Need Regular Water Changes
Fact: Regular Water Changes Are Critical for Goldfish Health
Some people believe that goldfish tanks don’t need frequent water changes, but that couldn’t be further from the truth. Because goldfish produce so much waste, it’s essential to perform regular water changes to keep the ammonia and nitrate levels in check.
- How often to change the water: I recommend doing a 25-30% water change every week for a well-stocked goldfish tank. This helps maintain stable water parameters and keeps your goldfish healthy. Don’t forget to use a water conditioner to remove chlorine and chloramines from tap water!
For more tips, read How to Perform Water Changes in Goldfish Tanks.
Myth 9: Fancy Goldfish Need the Same Care as Common Goldfish
Fact: Fancy Goldfish Have Special Care Requirements
Fancy goldfish, such as Orandas, Ranchus, and Fantails, are bred for their unique body shapes and long fins. However, these traits make them more delicate than common goldfish, meaning they require more attention and care.
- Why fancies need special care: Fancy goldfish are prone to swim bladder problems due to their compact bodies, and their flowing fins make them slower swimmers. This means they are more vulnerable to digestive issues and may need a diet that includes more fiber (like fresh veggies) to help prevent constipation.
For more on caring for fancy goldfish, check out Fancy Goldfish Care Guide.
Myth 10: Goldfish Don’t Have Personalities
Fact: Goldfish Are Surprisingly Social and Intelligent
Many people think goldfish are just simple creatures that swim around aimlessly, but in my experience, goldfish are surprisingly intelligent and interactive! They can recognize their owners, learn feeding schedules, and even be trained to do tricks like swimming through hoops.
- Building a bond with your goldfish: Spend time watching and interacting with your goldfish, and you’ll soon see their unique personalities shine through. They may come to the front of the tank when they see you or follow your hand during feeding times. Some goldfish even learn to recognize their names!
For fun goldfish training tips, check out How to Train Your Goldfish.
Goldfish are fascinating, intelligent, and long-lived pets, but keeping them happy and healthy requires the right care and environment. By understanding the common myths and focusing on the facts, you can ensure your goldfish thrive for years to come. Whether you’re just starting with goldfish or have been keeping them for a while, following the proper care guidelines will lead to a healthier and more enjoyable experience for both you and your fish.
For more detailed care tips, visit Complete Goldfish Care Guide.
FAQs
1. Can goldfish live without a heater?
Yes, goldfish are cold water fish, so they don’t usually need a heater. However, it’s important to keep the water temperature stable and not let it drop below 60°F.
2. How big can goldfish get?
In the right environment, goldfish can grow up to 6-10 inches, and some varieties can grow even larger, especially in outdoor ponds.
3. How often should I feed my goldfish?
Goldfish should be fed once or twice a day. Only offer as much food as they can eat in 2-3 minutes to avoid overfeeding and water quality issues.
4. Can I keep multiple goldfish together?
Yes, goldfish are social fish and enjoy the company of other goldfish. Just make sure you have a large enough tank to accommodate their growth and waste production.
5. Why is my goldfish tank cloudy?
Cloudy water is often caused by overfeeding, excess waste, or poor filtration. Performing regular water changes and maintaining a good filter can help resolve the issue.
